Yet another cyclic storm, looking towards the northwest. Visibilities and contrast were low in this northern Kansas storm, but we can make out a distant, rope-like tornado just left of center (about 6 miles to our west-northwest, and a wall cloud and developing funnel on the extreme right, about 3 miles to the north-northwest.

Minutes later, tornado #2 has touched down to our north-northwest whereas tornado #1 has lifted. This second tornado was producing significant damage at this time.

Moving closer, we are looking north from within 1/2 mile at tornado #2. It was changing rapidly in appearance as it quickly evolved into a large multiple vortex tornado. The huge vortex to the right of the road developed and dissipated within a minute, as another sub-vortex was forming to the left of the road. The tornado had become violent and leveled several farms. Early warnings were provided by excellent spotter reports.

Below is a storm which seemed to defy most of what we have said about cyclic storms! Looking north, note tornado #1 (with clear slot) at the south end of the precipitation area, tornado #2 east of the precipitation (extreme right), and wall cloud/developing tornado #3 in the visual distance between #1 and #2, and northeast of the precipitation area!

Thus, instead of a 20 minute gap we have concurrent mesocyclones on three different thunderstorm flanks! There are always exceptions to just about any "rule of thumb" we can make about severe thunderstorms.

introduction

Terms for using data resources. CD-ROM available. Credits and Acknowledgments for WW2010. Department of Atmospheric Sciences (DAS) at the University of Illinois at Urbana-Champaign.

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